According to a case series that was published in "Infectious Diseases," a 5-day isolation period may not be sufficient for omicron-infected patients to receive negative test results. More than 25% of the people exhibited a positive rapid antigen test 7-10 days following their initial positive test, with even greater proportions of persistent positivity in people with novel omicron BA.2 variant and symptomatic infections. Researchers carried out this study to estimate the percentage of COVID-19 infected people whose rapid antigen test was still positive seven days after diagnosis.

College athletes who were COVID-19 positive were included. To assess if they could cease their isolation period, volunteers received rapid antigen testing beginning seven days after their diagnosis. Identification of SARS-CoV-2 variant by campus wastewater analysis, status of the symptom, and rapid antigen test results were the major outcomes ascertained. The study comprised 264 student athletes, representing 268 infections (66% [n = 177] symptomatic, 34% [n = 91] asymptomatic; mean [standard deviation] age, 20.1 [1.2] years; range, 18-25 years).

Of them, 53% [n = 140] of the student athletes were female. Notably, 67 (27%) of the 248 infections among those who had a day 7 test still had positive results. In comparison to those who were asymptomatic, patients with symptomatic infections had a considerably higher likelihood of testing positive on day 7 (11% vs. 35%). Additionally, patients with the BA.2 variant had a 40% higher chance of testing positive on day 7 than those infected with the BA.1 variant (21%).

Rapid antigen testing remained positive in 27% of the patients following 7 days of isolation, indicating that the Centers for Disease Control and Prevention (CDC) suggested 5-day isolation interval may not be enough to stop the continuous transmission of the virus. To find out if these findings hold true in a more varied population and in later variants, additional research is required.

To prevent infected patients from prematurely exiting isolation, rapid antigen testing may be used to help with the decision to discontinue isolation.